Motor learning strategies in basketball players and its implications for ACL injury prevention:a randomized controlled trial

Adding external focus of attention (EF, focus on the movement effect) may optimize current anterior cruciate ligament (ACL) injury prevention programmes. The purpose of the current study was to investigate the effects of an EF, by a visual stimulus and an internal focus, by a verbal stimulus during unexpected sidestep cutting in female and male athletes and how these effects remained over time.Ninety experienced basketball athletes performed sidestep cutting manoeuvres in three sessions (S1, S2 and S3). In this randomized controlled trial, athletes were allocated to three groups: visual (VIS), verbal (VER) and control (CTRL). Kinematics and kinetics were collected at the time of peak knee frontal plane moment.Males in the VIS group showed a larger vertical ground reaction force (S1: 25.4 +/- 3.1 N/kg, S2: 25.8 +/- 2.9 N/kg, S3: 25.2 +/- 3.2 N/kg) and knee flexion moments (S1: -3.8 +/- 0.9 Nm/kg, S2: -4.0 +/- 1.2 Nm/kg, S3: -3.9 +/- 1.3 Nm/kg) compared to the males in the VER and CTRL groups and to the females in the VIS group (p <0.05). Additionally, the males in the VIS group reduced knee valgus moment and the females in the VER group reduced knee varus moment over time (n.s.).Male subjects clearly benefit from visual feedback. Females may need different feedback modes to learn a correct movement pattern. Sex-specific learning preferences may have to be acknowledged in day by day practice. Adding video instruction or feedback to regular training regimens when teaching athletes safe movement patterns and providing individual feedback might target suboptimal long-term results and optimize ACL injury prevention programmes.I.